The gallbladder pain is typically located in the right side, below the ribcage on the front side, and can be felt going towards the back, also below the ribcage.
The pain usually comes and goes, and is typically made worse with meals (particularly if there is a lot of fat in the meal).
The kidney stone pain is on the back side (right or left), below the ribcage as well, and it can be felt going towards the groin (on the same side of the back pain). The pain can also come and go, but is not related to meals. The urine may have some blood microscopically (or sometimes you can even see the urine turn pink / red because of blood).
The easiest way to differentiate them is with an abdominal ultrasound, and a urine test. Talk to your primary care physician to get it done. If you have any fevers you should go promptly to the emergency room.
Hope that helped, let me know if you have any further questions, sincerely,

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